Table 2.
Weekday sleep characteristics of 583 Chinese adolescents* aged 11–20 years based on sleep diary by gender and Tanner stages.
| Gender/Tanner stages |
Age (years) mean (SD) |
Bedtime |
Sleep latency |
Wake-up time |
TST§ (hour) |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | median (IQR†) |
10th | 90th | median (IQR†) |
10th | 90th | median (IQR†) |
10th | 90th | median (IQR†) |
10th | 90th | ||
| Male | ||||||||||||||
| I | 13.9 (1.1) | 58 | 20:38 (80) | 19:30 | 22:00 | 11.5 (10.0) | 5.0 | 30.0 | 6:00 (46) | 5:20 | 7:00 | 8.9 (1.8) | 7.8 | 11.3 |
| II | 15.2 (1.3) | 63 | 21:18 (60) | 20:18 | 23:00 | 13.3 (13.5) | 5.0 | 30.0 | 6:00 (60) | 5:19 | 7:35 | 8.5 (1.8) | 6.5 | 9.8 |
| III | 15.2 (1.1) | 68 | 21:27 (61) | 20:00 | 23:00 | 15.8 (15.8) | 6.7 | 32.5 | 6:00 (40) | 5:20 | 6:50 | 8.3 (1.3) | 6.9 | 9.8 |
| IV | 16.6 (1.6) | 62 | 22:00 (75) | 21:00 | 23:08 | 15.8 (14.8) | 8.0 | 36.0 | 6:30 (84) | 5:35 | 8:12 | 8.2 (1.8) | 6.6 | 11.0 |
| V | 19.0 (1.1) | 56 | 21:57 (115) | 20:24 | 23:54 | 23.8 (18.6) | 5.0 | 56.0 | 8:00 (90) | 6:34 | 9:30 | 9.5 (2.7) | 7.3 | 11.5 |
| Female | ||||||||||||||
| I | 12.9 (0.7) | 9 | 21:00 (43) | 19:45 | 21:17 | 10.0 (4.6) | 5.0 | 23.3 | 6:00 (3) | 5:30 | 7:00 | 8.9 (1.0) | 8.0 | 9.9 |
| II | 14.6 (1.2) | 71 | 21:06 (90) | 19:50 | 22:30 | 11.6 (15.0) | 5.0 | 30.0 | 6:00 (40) | 5:30 | 7:00 | 8.5 (1.8) | 7.1 | 10.2 |
| III | 15.9 (1.3) | 110 | 21:30 (68) | 20:30 | 23:00 | 12.5 (16.0) | 5.0 | 30.0 | 6:15 (119) | 5:30 | 8:12 | 8.6 (1.8) | 6.9 | 10.7 |
| IV | 16.6 (1.7) | 65 | 21:43 (90) | 20:30 | 23:30 | 10.0 (12.7) | 5.0 | 46.0 | 6:20 (116) | 5:30 | 8:22 | 8.5 (1.3) | 7.0 | 10.5 |
| V | 19.2 (1.4) | 21 | 22:30 (42) | 21:08 | 23:12 | 18.0 (13.0) | 5.0 | 32.0 | 8:16 (102) | 6:08 | 9:18 | 9.3 (1.9) | 7.6 | 10.6 |
*
Sample size varied from 621 to 583 due to missing Tanner stage data.
§
TST (Total Sleep Time) = wake-up time − bedtime − sleep latency.
†
IQR: Intraquartile range in minutes for bedtime and wake-up time and in hours for TST.